Stomach pain after eating, need to be alert to gastritis, gastric and duodenal ulcer, acute gastroenteritis and other diseases. 1. Gastritis: acute or chronic inflammation of the gastric mucosa caused by stress, alcohol, trauma, Helicobacter pylori infection, autoimmunity and other factors. It can manifest as epigastric pain, abdominal distension, belching, nausea, loss of appetite, gastrointestinal bleeding, emaciation and other symptoms. It can be divided into acute gastritis, chronic gastritis and special type of gastritis. 2. Gastric and duodenal ulcer: refers to the inflammatory defects occurring in the gastrointestinal mucosa, usually related to the digestive action of gastric acid in gastric juice, the lesion penetrates the mucous membrane muscle layer or reaches a deeper level. It often occurs in the lesser curvature of the stomach, the pyloric region of the stomach and the duodenal bulb. It can be manifested as epigastric pain, the nature of the dull pain, burning pain, distension, severe pain, hunger-like discomfort and so on. 3. Acute gastroenteritis: refers to acute inflammation of the gastrointestinal mucosa caused by bacteria, viruses, fungi, etc. It is usually triggered by eating unclean, cold or irritating foods, such as ice cream, spoiled tofu, spicy hot pot. It can manifest as nausea, vomiting, abdominal pain, diarrhea and so on. Stomach pain after eating may also be bacillary dysentery, ulcerative colitis and other diseases, it is recommended to consult a doctor to clarify the diagnosis, under the guidance of the doctor for targeted treatment.